CVE-2020-4037Open Redirect in OAuth2 Proxy
- 4.3MediumCVSS base score
- 0.90%Exploitation in 30 daysEPSS · top 40% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In OAuth2 Proxy from version 5.1.1 and less than version 6.0.0, users can provide a redirect address for the proxy to send the authenticated user to at the end of the authentication flow. This is expected to be the original URL that the user was trying to access. This redirect URL is checked within the proxy and validated before redirecting the user to prevent malicious actors providing redirects to potentially harmful sites. This has been fixed in version 6.0.0.
Timeline
ID reserved
By GitHub_M
- 6 months later
· 6 months later
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N |
| NVDNVD · Modified | 3.1 | Medium5.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.90% · top 40% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.
Affected products
- affected >= 5.1.1, < 6.0.0
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/oauth2-proxy/oauth2-proxyGHSA-5m6c-jp6f-2vcv (opens in a new tab)
References
References2
- https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-5m6c-jp6f-2vcv (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/oauth2-proxy/oauth2-proxy/commit/ee5662e0f5001d76ec76562bb605abbd07c266a2 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-2449 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-5m6c-jp6f-2vcv (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2020-4037)Record last updated .